1. Field of the Invention
This invention relates to vehicle seat back latch mechanisms, particularly to inertia-responsive, seat back latch mechanisms, and more particularly to vehicle-sensitive, inertia-responsive seat back latch mechanisms.
2. Description of the Prior Art
The prior art discloses the exploitation of inertia and gravity to provide latching mechanisms for vehicle seat backs. However, none of these prior art mechanisms employs an unattached, inertia-responsive mass, nor do they provide a latching mechanism which will permanently lock the vehicle seat to prevent tilting of the seat back subsequent to the deceleration of the vehicle.
While all prior art inertia-responsive mechanisms will lock a seat back and prevent forward tilting of the seat back during a sudden deceleration, such as is experienced during a frontal crash, they are inoperative when deceleration is no longer occurring. Because all seat backs will exhibit some flexibility during a frontal crash, the locked seat back will flex forward during the first stage of the crash, thereby absorbing energy. During the intermediate stage of the crash, the seat back will then flex back, through its original position, and beyond to a new back, flexed position. At this stage of the crash, the vehicle has stopped decelerating or is slowly decelerating. Now the seat back, in its back flexed position, flies forward again, but because the vehicle is no longer quickly decelerating, the latching mechanism will not prevent the seat back from moving to its fully forward position. This is known as seat back rebound, and results in serious passenger injuries notwithstanding the presence of conventional seat back latch mechanisms.
It is, therefore, a primary object of this invention to provide a new vehicle-sensitive, inertia-responsive seat back latch mechanism.
Yet another object of this invention is to provide a new seat back latch mechanism which will prevent seat back rebound.
Yet another object of this invention is to provide a new seat back latch mechanism which employs an unattached, inertia-responsive mass.